Tech Physicists Flying Into Tropical Storms

SOCORRO, N.M. August 19, 2010 – Three New Mexico Tech scientists are spending six weeks in the U.S. Virgin Islands studying hurricanes.

Physics professor Dr. Dave Raymond is the principal investigator on a National Science Foundation project to study the atmospheric conditions that tend to form tropical storms. Staff physicist Dr. Carlos Lopez and doctoral student Saska Gjorgjievska are contributing to the effort.

To decipher which storms could bring danger, and which will not, atmospheric scientists are in the tropics, observing these systems as they form and dissipate – or develop into hurricanes.

Physics professor Dr. Dave Raymond ready for an air mission in the Gulfstream V in St. Croix.

By learning to identify which weather systems are the most critical to track, the efforts may ultimately allow for earlier hurricane prediction, and add several days to prepare for a hurricane's arrival.

The Pre-Depression Investigation of Cloud Systems in the Tropics, or PREDICT, mission will run from August 15 to September 30, 2010, the height of hurricane season.

“The fun part is being the first to observe or notice new things,” Lopez said. “It’s very exciting to try to explain things that haven’t been explained yet. Hopefully we’ll get some storms passing by that are within our range.”

Raymond will be aboard mission aircraft, selecting times and locations to launch “drop sondes” into storm formations. Drop sondes are instruments that gather atmospheric data as they parachute into the ocean. These sondes measure temperature, humidity, wind speed, wind direction, pressure and location (by GPS), then transmit the data via radio.

“Tropical storms form out of pre-existing disturbances,” Raymond said. “The current theory being tested is that tropical storms form in a protected region in the core when the circulation of easterly waves act to protect the core from dry air. Tropical storms love moist air.”

Raymond will fly 15 to 20 missions, dropping 20 to 30 sondes on each flight.

“It feels like dropping $1,000 bills out of an airplane,” he said. “The sondes cost more than $700 and there’s no way to recover them.”

The mission includes multiple aircraft; Raymond will be aboard a Gulfstream 5. Lopez will also be an on-board scientist.

“We’ll be flying around these systems that are not yet tropical depressions, but have the potential to become one,” Lopez said.

After successful missions, Raymond, Lopez and Gjorgjievska will analyze the data in order to put the prevailing theories to the test. In addition to advancing the general understanding of tropical storms, the data collected on this mission will provide vital material for Gjorgjievska’s dissertation.

The atmosphere in the tropics is typically very dry. Lopez compared the localized moist air in storms to a kangaroo’s pouch – protected from the surrounding dry air.

“This region is proposed as the sweet spot where a storm can generate,” he said.

A key to a successful mission is picking the optimum times and locations to deploy the drop sondes. While evaluating input from several people observing the system, Raymond will direct the pilot to the best location and decide when to drop the sondes.

The project scientists represent seven universities and several research agencies, including NASA, the National Oceanic and Atmospheric Administration and the National Center for Atmospheric Research. This field test is one in series of data gathering excursions in the project, which is now in its third year.